The Symphony Trial- Sibrafiban vs. aspirin to yield maximum protection from ischemic heart events post acute coronary syndromes is a multi-center drug trial comparing the efficacy of Sibrafiban, an oral platelet glycoprotein IIb/IIIa antagonist to aspirin as therapy for the prevention of secondary vascular events in patients after an acute coronary syndrome. This study is now closed to recruitment and the next phase is a phase III double blind study.